High pressure fluid apparatus has long been used for cleaning surfaces. Typically, the apparatus includes a housing permitting fluid communication between a fluid source and a high pressure outlet. Further, an alternate fluid communication route is provided between said fluid source and a lower pressure fluid dump, or exhaust. A trigger operated valve mechanism governs the fluid route. Known references are U.S. Pat. Nos. 4349154, 4136854, 4017576, 3986523, 3885739, 3698422, 3679332, 3672575, 3614060, 3181474, 2308347, and 4602740. These valve mechanisms usually have included a valve, a valve guide and a valve seat. Earlier mechanisms sometimes used the walls of the housing as the valve guide. One problem with that arrangement was the difficulty and expense of repair. A more recent development was the provision of a removable cartridge containing the valve, and a unified valve guide and valve seat. Even here, the expense of replacing and repair of the common guide and seat was substantial. Further, machining costs of fabrication were high. Additionally, removal of the valve mechanism from the housing sometimes proved difficult. Applicant's invention is directed to the two-fold problem.